JPS5837109Y2 - Musical tone control device for electric instruments - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a musical tone control device for an electric musical instrument that uses air pressure to control volume, timbre, etc.

Various musical tone control devices for electric musical instruments have already been proposed, which electrically detect air pressure and control musical tones based on the detected signal.

However, they are difficult to detect, such as exhalation pressure detection.
Both are designed to detect air pressure increased by blowing air.

Therefore, if you try to electrically convert the air pressure that repeatedly increases and decreases due to air blowing and suction, such as the bellows of an accordion, to detect it as a voltage, the detection output will be zero when neither air is blown nor sucked, and the air pressure will increase and decrease repeatedly due to air blowing and suction. If the pressure is positive, the output voltage will also be positive, but conversely, if the suction wind pressure is negative, the output voltage will also be negative, so if this continues, it will be difficult to control the volume by suction wind pressure.

Therefore, either a pressure-sensitive element is provided to detect the wind pressure separately for blowing and breathing, and only the positive potential is detected from among the respective outputs shown by the solid line and the broken line in Fig. 1, or one pressure-sensitive element is used. It is conceivable to convert the negative potential part of the output shown by the solid line in FIG. 2 into a positive potential as shown by the two-dot chain line.

1 and 2 are characteristic diagrams illustrating the relationship between the wind pressure P and the output voltage V of the pressure-sensitive element, with the horizontal axis representing the wind pressure P and the vertical axis representing the voltage ■.

As is clear from these figures, the zero setting of the voltage is distorted due to mechanical errors and the influence of temperature, and with the method described above, it is not possible to apply the same absolute pressure during air blowing and suction. Even if the detection voltage was different, it was not possible to perform stable control when switching between air blowing and suction.

This idea was made in view of the above points, and it was created by forming an air path that flows in one direction for the blowing/suction reciprocating action, and installing a wind pressure detection element in the air path that flows in one direction. Therefore, it is an object of the present invention to provide a musical tone control device for an electronic musical instrument that can stably detect the wind pressure of blowing and inhaling, and use the detected pressure signal to control the volume, timbre, etc. of musical tones.

Embodiments of this invention will be described below with reference to the accompanying drawings.

FIG. 3 is a side sectional view showing one embodiment of the musical tone control device for an electric musical instrument according to this invention.

Reference numeral 1 denotes an air blowing/intake pipe main body made of synthetic resin or the like with a bottom shape, one end of which is made thinner to serve as an air air intake port 2, and the other end is closed by a bottom plate 3, which has an air intake hole 4 that communicates with the outside air. An exhaust hole 5 is provided.

The air passage of the air supply/intake pipe main body 1 includes a partition plate 6 provided on the side of the air supply/intake port 2, and a partition plate 7 that divides the air passage between the partition plate 6 and the bottom plate 3 into two vertically. It is divided into three rooms by.

For convenience of explanation, the air path from the air supply/intake port 2 to the partition plate 6 will be referred to as a room A, the air path above the partition plate 7 will be referred to as a room entrance, and the air path below will be referred to as a room.

The partition plate 6 is provided with an air supply hole 8 that communicates between rooms A and D, and an intake hole 9 that communicates between rooms A and C. Each is fitted with a valve 10.11 which restricts the air flow in one direction.

The partition plate 7 is provided with a ventilation hole 12, and an opening/closing hole with appropriate rigidity is provided below the ventilation hole 12 in FIG. One end of the valve 13 is secured.

A pressure detection element 14 is bonded or built into a device that is subjected to bending stress when the on-off valve 13 receives wind pressure, and both electrode lead wires 15 from the pressure detection element 14 are connected via lug terminals 16 attached to the partition plate 7. , a signal detection circuit (not shown) that passes through the bottom plate 3 and is led out of the air path by a lead wire 17;
Wired to the control voltage generation circuit, etc.

As the pressure detection element 14, for example, a piezoelectric element such as a piezoelectric ceramic that generates a voltage signal due to mechanical strain, or a pressure sensitive resistance element such as a nickel alloy wire whose electrical resistance value changes depending on strain, etc. is used.

Pressure detection valve 1 by on-off valve 13 and pressure detection element 14
8 are made up.

The suction hole 4 of the bottom plate 3 is provided with a valve 19 on the room entrance side.
Further, the discharge hole 5 is provided with a valve 20 on the outside air side, so that the air flow is unilaterally passed from the outside air side to the room entrance, or from the room C side to the outside air side.

The air supply/intake port 2 of the air/intake pipe main body 1 is connected to a wind generator (not shown), such as an accordion, which alternately increases and decreases the pressure by reciprocating motion.

When air is blown from the wind generator, the pressure inside the room increases,
The valve 11 closes the intake hole 9, the valve 10 is opened by the pressure, and air flows into the room entrance from the ventilation hole 8.

When the pressure at the chamber opening is increased, the valve 19 closes the suction hole 4,
The pressure detection valve 18 is pushed down to allow air to flow into the room C from the ventilation hole 12, and the valve 20 is opened and air is exhausted from the exhaust hole 5.

That is, the air flow at this time follows the path shown by the solid line arrow in FIG.

Next, when the wind generator takes in air, the inside of the room A is forced, valve 10 closes, and valve 11 opens.

Subsequently, the valve 20 closes the exhaust hole 5 due to the reduced pressure in the room C, so the pressure detection valve 18 is sucked downward and pushed down in the same way as when blowing air, and the valve 19 opens and closes the intake hole 4.
The air is sucked in from outside, passes through the ventilation hole 12 and the intake hole 9, and flows into the wind generator from the air supply intake port 2.

That is, the air flow at this time follows the path shown by the broken line arrow in FIG.

In this way, the direction of the airflow passing through the ventilation hole 12 during either ventilation or intake is one direction from top to bottom in FIG. The pressure detection valve 18 deflects proportionally, increasing its opening angle.

Therefore, the pressure detection element 1 attached to the on-off valve 13
4 senses the stress applied to the on-off valve 13 and detects it as an electrical signal.

This detection signal is subjected to processing such as amplification and used as a control voltage signal for a voltage-controlled variable gain amplifier (hereinafter abbreviated as VCA) constituting a musical tone forming circuit, for example, in order to adjust the volume.

FIG. 4 is a block diagram showing an embodiment of a musical tone forming circuit for an electronic accordion to which the musical tone control device for an electric musical instrument according to the present invention is applied.

In the figure, 21 is a voltage controlled oscillator (hereinafter abbreviated as VCO) whose oscillation frequency is changed by a control voltage from a key circuit 26, 22 is a voltage controlled filter (hereinafter abbreviated as VCF), and 23 is a VCA.

When a key on the accordion is pressed during a performance, key circuit 2
A control voltage corresponding to that key is generated from 6, and ■CO
The oscillation frequency of 21 is controlled to output a predetermined pitch signal.

This pitch signal has a tone color, an envelope, etc. formed by the VCF 22 and VCA 23, and is output as a musical tone from the speaker 25 via the amplifier 24.

Further, the air supply/intake port 2 of the above-mentioned musical tone control device is connected to the accordion bellows, and the change in air pressure due to the reciprocating movement of the bellows is detected by the pressure detection element 14, and the detected output signal is sent to the control voltage generation circuit 27. Enter.

The detection output signal is subjected to processing such as amplification by the control voltage generation circuit 27, and is applied as a control voltage signal to, for example, the VCA 20 to control the volume of the musical tone and form the envelope of the musical tone.

Note that this control voltage signal is applied to the VCO 21 or VCF 22 simultaneously or separately as shown by the broken line,
The pitch or timbre of musical tones may also be controlled.

As described above, according to this invention, only one pressure-sensitive element is used to respond to the increase or decrease in pressure due to air blowing or intake.
Detects the pressure of blowing and sucking evenly without bias, and adjusts the volume of musical tones,
It is possible to control the timbre, etc., and it has a simple structure and is easy to adjust.

If this is used in an electronic wind instrument, it can be played by blowing or sucking, like a harmonica.Also, like an electronic accordion, changes in air pressure due to the reciprocating movement of the bellows can be picked up, and the VCO, VCF .

By controlling the VCA and the like, it is possible to obtain a musical tone closer to that of a natural musical instrument.

Furthermore, if you connect a device that reciprocates like a cylinder and piston and repeats intake and exhaust, and change the operating speed of the piston manually depending on the song, you can create an envelope for a stringed instrument like a violin. can also be made.

[Brief explanation of the drawing]

Figure 1 is a wind pressure-output voltage characteristic diagram when separate pressure detection elements are provided for air supply (solid line) and intake (broken line), and Figure 2 is a wind pressure-output voltage characteristic diagram when one pressure detection element is used, and negative potential is changed to positive potential. 3 is a side sectional view showing an embodiment of this invention, and FIG. 4 is an implementation of a musical tone forming circuit for an electronic accordion to which this invention is applied. FIG. 2 is a block diagram illustrating an example. 1...Blower/intake pipe body, 2...Air intake port, 4...Suction hole, 5...Exhaust hole, 8... ...Air supply hole, 9...Intake hole, 10
．． 11.19.20... Valve, 12...
...Ventilation hole, 13...Opening/closing valve, 14...
・Pressure detection element, 18...Pressure detection valve.

Claims (1)

[Scope of utility model registration request] One pressure detection valve is installed in the air passage where air intake and air supply are repeated, and a plurality of air flow control valves are installed so that the airflow passing through the pressure detection valve section flows in one direction regardless of intake and air supply. A musical sound control device for an electric musical instrument, characterized in that the reciprocating motion of air intake and air supply is detected as pressure in one direction, and the volume, tone, etc. of musical tones can be controlled by the detected pressure signal. .